muster up vs come up

muster up and come up both are verbs.

Word	Noun	Adjective	Verb	Adverb
muster up	No	No	Yes	No
come up	No	No	Yes	No

As verbs, muster up and come up are synonyms defined as:

Other synonyms of muster up include muster, rally, summon.

muster up (verb)	come up (verb)
gather or bring together	result or issue
	start running, functioning, or operating
	gather or bring together
	gather (money or other resources) together over time
	bring forth, usually something desirable
	come up, of celestial bodies
	come to the surface
	move toward, travel toward something or somebody or approach something or somebody
	move upward
	get something or somebody for a specific purpose
	originate or come into being
	be mentioned